Statt Link in der Vorschau das Bild?

<div class="box48 wbbPostPreview">
	{if $post->getUserProfile()->getAvatar()}
		<a href="{link controller='User' object=$post->getUserProfile()->getDecoratedObject()}{/link}" class="framed">{@$post->getUserProfile()->getAvatar()->getImageTag(48)}</a>
	{/if}


	<div>
		<div class="containerHeadline">
			<h3><a href="{link controller='User' object=$post->getUserProfile()->getDecoratedObject()}{/link}">{$post->username}</a> <small>- {@$post->time|time}</small>
				{if MODULE_LIKE && $__wcf->getSession()->getPermission('user.like.canViewLike') && ($post->likes || $post->dislikes)}<span class="likesBadge badge jsTooltip {if $post->cumulativeLikes > 0}green{elseif $post->cumulativeLikes < 0}red{/if}" title="{lang likes=$post->likes dislikes=$post->dislikes}wcf.like.tooltip{/lang}">{if $post->cumulativeLikes > 0}+{elseif $post->cumulativeLikes == 0}±{/if}{#$post->cumulativeLikes}</span>{/if}
			</h3> 
		</div>

		{if $labels|isset}
			<ul class="labelList">
				{foreach from=$labels item=label}
					<li class="label badge{if $label->getClassNames()} {$label->getClassNames()}{/if}">{lang}{$label->label}{/lang}</li>
				{/foreach}
			</ul>
		{/if}

		<div>{@$post->getFormattedMessage()|truncate:300:'...'}</div>

		{event name='previewData'}
	</div>
</div>